The overall objective of this investigation is to perform genetic studies of asthma. We will study 100 nuclear families whose members have asthma, including men, women and children 5 years and older of all ethnic backgrounds. All members of the families will be characterized using questionnaires, allergy skin testing, lung function studies, and blood studies for serum IgE levels, and genomic DNA. With this information we will identify and characterize the gene(s) and their products which are involved in the production of asthma. This information will further our understanding of asthma and provide new methods for its diagnosis and treatment.